We are requesting funds through the Shared Equipment Evaluation Program (ShEEP) under the Research Equipment Management program offered by the Office of Research and Development for purchase of an EchoMRI 4in1 Body Composition Analyzer (EchoMRI LLC, Houston TX, USA) as an upgraded replacement for an older version that will be moving to a new institution in 2018. The new system allows for the measurement of body composition, specifically fat mass, lean mass, free water, and total body water, in live mice- and rat-sized animals. In addition, the EchoMRI 4in1 analyzer is also able to measure the composition of tissue samples / organs and biopsies (small tissue samples), which is not a feature of our current, outdated system. By using minimal restraint in live animals, experimenters are able to conduct long-term, longitudinal studies, without causing undue stress. Compared to other systems that require immobility for the measurement of body composition, typically through the use of anesthetics, this system can measure body composition in unrestrained animals by limiting their mobility within the specialized specimen tube. This equipment will be housed within the Minneapolis VAHCS Research Services Veterinary Medical Unit, and unlike other systems, does not require special shielding. This equipment will allow for the study of organ and tissue composition, as it related to cancer, obesity, and various other disease progressions. In addition, the quick measurement times for specimens (< 3min), make it possible to complete control and test paradigms more quickly, thereby reducing variability between control and test groups. This in turn will allow greater throughput of all users? experimental designs, increasing the productivity of the Minneapolis VAHCS investigators. The use of this equipment will compliment an existing inventory of multiuser based instruments with the end goal of increasing the efficiency of and supporting translational VA research. Dr. Patricia Bunney will oversee the administration and usage of the equipment under the full support of Minneapolis VAHCS Director, Mr. Patrick J. Kelly and the Research & Development Committee Chair, Dr. Ronald Bach. The major and minor user groups for this equipment span multiple VA research disciplines and represents both basic and translational research in areas such as: aging, addiction, cancer, neuroscience, stem cell therapies and obesity. The VA funded users combined will use at least 75% of the instrument capacity. The minor users group will occupy 25% of instrument capacity. The ability for Minneapolis VAHCS to continue to remain one of the largest and most active research programs in the VAHCS depends on the ability of its investigators to gain access to the newest generation of high-sensitivity, high-resolution instruments. The acquisition of the EchoMRI 4in1 Body Composition Analyzer would accelerate and enhance the rate at which researchers from multiple disciplines could acquire, analyze, and understand data with the long-term goal of benefiting the unique health care needs of US Veterans. This not only benefits the progress of VAHCS research in general but it would benefit the health care of all Americans.